Today, many portable devices or vehicle head units are capable of determining their respective locations using one or more of various locating techniques. For example, some portables devices and/or vehicle head units are equipped with a Global Positioning System (GPS) chip to determine the latitude, longitude, and elevation of the portable devices and/or vehicle head units based on signals received from several GPS satellites. Some portable devices and/or vehicle head units are instead (or additionally) capable of determining their respective locations using signals from fixed or semi-fixed terrestrial elements having known locations, such as fixed cellular infrastructure elements (e.g., cellular tower base stations), Wi-Fi access points (APs) or “hotspots,” etc.